KUALA LUMPUR, Malaysia — A man traveling with a stolen passport on a missing Malaysia Airlines jetliner was an Iranian teenager trying to migrate to Germany and is not believed to have any terrorist links, police said Tuesday.

The announcement is likely to dampen, at least for now, speculation that the disappearance of the Boeing 777 was linked to terrorism. Police said a second passenger also traveling with a stolen passport has not been identified. Both bought their tickets in Thailand and entered Malaysia together.

No debris from the plane has been found. On Tuesday, baffled authorities expanded their search to the opposite side of Malaysia from where it disappeared more than three days ago with 239 people on board.

The airline says the pilots did not send any distress signals, suggesting a sudden and possibly catastrophic incident. Speculation has ranged widely about possible causes, including pilot error, plane malfunction, hijacking and terrorism.

News that two of the passengers were traveling with stolen passports immediately fueled speculation of foul play. However, Malaysian police chief Khalid Abu Bakar said at a news conference Tuesday that investigators had determined one was a 19-year-old Iranian, Pouria Nourmohammadi Mehrdad, who was planning to enter Germany to seek asylum.

"We believe he is not likely to be a member of any terrorist group," Khalid said.

He said the young man's mother was waiting for him in Frankfurt and had been in contact with police. He said she contacted Malaysian authorities to inform them of her concern when her son didn't get in touch with her.